Pneumatic power tools are commonly employed in a variety of work places to accomplish a diverse assortment of tasks. Typical pneumatic power tools include pneumatic fasteners such as pneumatic nail guns and pneumatic staple guns. These pneumatic fasteners often employ piston assemblies coupled with valve assemblies to provide the force desired to drive a fastener into a surface. It is understood that the flow of compressed air into and through these pneumatic tools must be controlled and directed.
Unfortunately, pneumatic fasteners may typically employ functional features for controlling and directing the air flow which involve expensive and time consuming manufacturing processes and result in decreased performance characteristics. For example, many pneumatic fasteners require a cross hole to be drilled and plugged or an angled hole to be drilled, both through an outer cap (e.g., aluminum cap), in order to get supply air from the air source, through the outer cap, and to the back side of the valve piston chamber. This may significantly increase manufacturing costs, which in turn may be passed on to the consumer.
Another problem associated with pneumatic fasteners, which employ the methods of getting the supply air to the valve piston chamber, as described above, is that these machined holes provide rough surfaces over which the air must travel. These rough surfaces may increase air flow turbulence/friction thereby reducing the efficiency of air flow travel and possibly decreasing the efficiency of the pneumatic fastener. Current solutions to overcome this friction problem typically involve the application of a lubricant to these surfaces. These lubricants may increase the cost of operating these pneumatic fasteners and decrease productivity as the pneumatic fasteners must halt operation in order to have the lubricant provided. This is an on-going problem as the lubricant has a limited useful lifespan and must be continuously replaced to assist in smoothing the surfaces over which the air flow must travel.
In a pneumatic fastener, an air inlet port is used to connect to an air supply hose to supply compressed air to the pneumatic fastener, and a separate exhaust port is used to let exhaust air of the pneumatic fastener exit to outside. This may increase the manufacture cost. Furthermore, the position of the exhaust port is often fixed on the pneumatic fastener. This may cause inconvenience to an operator. For example, when an operator operates the pneumatic fastener, the position of the exhaust port may happen to face the operator. As a result, the exhaust air blast exiting the pneumatic fastener may be directed toward the operator. Thus, it would be desirable to provide an adjustable exhaust assembly, which may be used as both an air inlet port and an exhaust port for a pneumatic fastener and may enable an operator to adjust the direction of exhaust exiting the pneumatic fastener as the operator desires.